Trends in pathogens and antimicrobial resistance in culture-proven neonatal sepsis over a decade (2015-2024): the impact of COVID-19 pandemic.

BACKGROUND: Neonatal sepsis remains a leading cause of mortality and long-term disability worldwide. The coronavirus disease 2019 (COVID-19) prevention measures effectively curbed viral transmission. However, evidence of their long-term impact on the pathogen spectrum and antimicrobial resistance in neonatal sepsis is limited. METHODS: In this single-center retrospective observational study at Henan Children's Hospital, 894 neonates with culture-confirmed sepsis (2015-2024) were enrolled. Using pandemic policy time points, we divided the study into three phases and compared pathogen spectrum and antimicrobial resistance. RESULTS: Among neonates with sepsis, preterm proportion increased from 32.5% to 46.2%. The pathogen spectrum shifted from Gram-positive to Gram-negative predominance. Coagulase-negative staphylococci (CoNS) detection declined from 36.6% to 9.8%, a trend consistent across preterm/full-term and early-onset/late-onset subgroups. Klebsiella pneumoniae (K. pneumoniae) maintained high resistance to third-generation cephalosporins, while Escherichia coli (E. coli) showed a numerical increase in ceftazidime resistance. In contrast, CoNS and Enterococcus faecium (E. faecium) remained susceptible to vancomycin and linezolid. E. coli maintained favorable susceptibility to carbapenems and piperacillin-tazobactam, whereas K. pneumoniae showed a fluctuating carbapenem resistance trend that initially increased then declined, though it remained susceptible to tigecycline. All-cause mortality increased from 1.4% to 5.4%, with Gram-negative bacteria predominating in fatal cases. CONCLUSION: Enhanced hand hygiene and contact isolation are consistent with a sustained decline in CoNS, but show limited association with changes in Gram-negative bacilli. Routine surveillance and optimized empirical therapy remain crucial for improving neonatal sepsis outcomes.